Valve bag



Sept. 8, 1953 R. F. BENNETT 2,651,451

VALVE BAG Filed April 18, 1950 Patented Sept. 8, 1953 VALVE BAG Richard F. Bennett, New Hope, Pa., assignor to Universal Paper Bag poration of Pennsylvania New Hope, Pa., a cor- Application April 18, 1950, Serial No. 156,593

1 Claim. 1

This invention relates to multi-ply valve bags. Multi-ply valve bags are commonly used in industry for the packaging and shipment of pulverent or granular materials such as cement, grain and the like. In valve bags one of the upper corners is provided with a folded construction which forms an open passageway through which a filling tube may be inserted to fill the bags. After the bag is filled, the tube is withdrawn and the wall of the passageway is pressed against the bag wall by the contents of the bag to from a more or less effective seal. Early examples of bags of this type are shown in Bates U. S. Patents Nos. 1,668,542 and 1,752,292.

The phrase more or less effective is used advisedly in describing the seal provided, and over a period of years many bag constructions have been devised to improve the effectiveness of the seal. Such constructions are well known in the art, and without pausing to describe them in detail, it may be said that they include the socalled valve extension type and sleeve valve type, both of which have had wide commercial use. In such types, the extension or sleeve is usually provided by an additional piece of material which must be inserted and secured to the valve itself. In both cases the extra material required for the extension or sleeve, together with the additional operations required to form and insert the same add substantially tothe cost of the bag.

It is an object of the present invention to provide a multi-ply bag having an improved valve which may be formed at a cost only slightly greater than that of an ordinary valve to provide a seal which is equally or more efiective than that provided by the more expensive valve extension and sleeve valve types of bag.

Other objects and advantages of the invention will appear hereinafter.

A preferred embodiment of the invention selected for purposes of illustration is shown in the accompanying drawings, in which,

Figure l is a front elevation of a corner of a bag having a valve therein.

Figure 2 is a plan view with the walls spread open to show the valve construction.

Figure 3 is a side elevation.

Referring to the drawings, the bag is a multiply bag consisting of a plurality of plies I, 2, 3 and 4. The bag is formed with a gusset 5 and the valve 6 is formed in the usual manner by folding the top corner material inwardly at the gusset. The top of the bag is closed in the desired manner, as by a binding strip 1 secured by stitching 8.

According to the present invention, the valve is provided with a series of parallel slits 9 extending outwardly from the inner edge thereof, said slits being spaced relatively closely, as for example from A" to apart. Each and every one of the plies of the material are slit so that the inner edge of the valve is in the form of a series of superimposed fringes comprising a multiplicity of flexible, independently movable fringe elements, all of which are free to adjust themselves in any direction depending on the forces to which they are subjected. They can move laterally to interleave themselves or they can move vertically to fill or close crevices through which leakage might otherwise occur. As a result a very effective seal is provided at a cost only negligibly greater than that of an ordinary valve. I

I am aware of the valve constructions described in Gadsden Australian Patent No. 22,108 and Contryman U. S. Patent No. 2,378,285, but both fail to attain the advantages of my invention. Both prior patents utilize single ply inserts to form. extensions which not only add to the cost of the bag, but provide only a single ply fringe which is relatively ineffective for sealing purposes. Gadsden, it is true, provides slits in the valve as well as in the extension, but the extension, being inserted between the plies of the valve itself, interferes with the freedom of movement of the fringe elements forming the fringed edge of the valve and detracts from the effectiveness which they would otherwise possess.

It will be understood that the invention may be variously modified and embodied within the scope of the subjoined claim.

I claim as my invention:

A valve bag comprising a multi-ply body having a longitudinal gusset and having a. top corner folded in at the gusset to form a multi-ply valve, said valve having a series of slits extending outwardly from the inner edge of each and every ply thereof forming a series of superimposed fringes comprising a multiplicity of flexible, independently movable fringe elements which are free to adjust themselves in any direction.

RICHARD F. BENNETT.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 921,664 Bates May 18, 1909 FOREIGN PATENTS Number Country Date 22,108 Australia Aug. 29, 1930 

